Mayor Bill de Blasio announced Monday that all education department employees — including teachers, administrators, cafeteria workers and custodians — must show proof that they have received at least one dose of COVID-19 vaccines by September 27th, two weeks after classes resume. The mandate will apply to 148,000 education department workers. The announcement coincided with the U.S. Food and Drug Administration granting full approval to the Pfizer-BioNTech vaccine. The new mandate goes further than the policy the mayor announced earlier this summer for all city workers, including teachers, that requires vaccination or weekly testing. It applies to the city’s traditional public schools and includes any charter schools that are co-located with them. The mandate does not apply to pre-k teachers at community-based organizations outside the city’s school buildings, bus drivers or private schools. The latter can set their own rules and are governed by the state.